The harrowing tragedy that recently befell 8-year-old Madyson "Maddy" Middleton is extremely unlikely -- statistically. But probability is no comfort to parents carrying memories of Newtown and Columbine. Maddy's killing has thrown parents and children into a maelstrom of fear, confronting a crime both unforeseen and unfathomable.

Grumpy investors have been sending messages of frugality not just to San Francisco-based McKesson, one of America's oldest companies, but to maturing tech companies such as Oracle, Salesforce.com and Yahoo.